# Science physics

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mandy drops a 2.0kg book from a height of 4.5m. how much work has gravity done on the book?

M=2.0kg
D= 4.5m

Not actually sure what to do next. Because none of the formulas work. I need work but I don't even know the force. To find force I need mass which I have but I don't have acceleration.

• Science physics - ,

The acceleration is due to gravity

g = 9.8 m/s^2

• Science physics - ,

The question is asking for work though. And the answer says it's 88J but I don't get how they got that as the answer

• Science physics - ,

work is in Joules

2.0kg * 9.8 m/s^2 * 4.5m = 88.2 kg-m/s^2 = 88.2N-m = 88.2J

work = force * distance
force = mass * acceleration

• Science physics - ,

Ohhh. That's what I missed. Okay thanks for explaining step by step. It helped a lot

• Science physics - ,

Ohhh. That's what I missed. Okay thanks for explaining step by step. It helped a lot

• Science physics - ,

Ohhh. That's what I missed. Okay thanks for explaining step by step. It helped a lot